Importance and utilization of colostrum

Kolostrum je prirodni koncentrat hranjivih i obrambenih tvari, imunoglobulina i faktora rasta. Kako jedinstveni sastojci i osobine kolostruma nisu specifične za vrstu, on može biti ljudima svih dobi izuzetna dopuna prehrani. Stoga je u ovom radu razmotren sastav kravljeg i humanog kolostruma, te glavni imunofaktori i faktori rasta koje kolostrum sadrži. Poseban je naglasak stavljen na terapijsko djelovanje kolostruma u prevenciji i liječenju nekih poremećaja.Colostrum is natural concentrate of nutritional and protection factors, immunoglobulins and growth factors. Since the unique components and characteristics of colostrum are not specific for species, colostrum can bee excellent food supplement for people of all ages. In this paper the composition of cow’s and human colostrum is discussed, as well as main imunofactors and growth factors in it. Special emphasis is given on therapeutic effect of colostrum in prevention and therapy of some disorders

Prebiotic substrates and lactic acid bacteria

Radi sve veće popularizacije proizvoda prirodnog podrijetla, osobito u području prehrane i prehrambenih aditiva, u posljednje je vrijeme intenzivirana uporaba sporo apsorbirajućih i neapsorbirajućih šećera kao supstrata za bakterije mliječne kiseline i kao prebiotika za ljudsku prehranu. Ljudsko debelo crijevo sadrži veliku koncentraciju bakterija (10000000000000 po gramu suhe tvari sadržaja debelog crijeva), a noviji radovi pokazuju da bifidobakterije i laktobacili, najbrojnije uobičajene anaerobne bakterije u mikroflori ljudskog debelog crijeva, korisno djeluju na zdravlje domaćina. Glavni čimbenik za razmnožavanje bifidobakterija u ljudskom probavnom sustavu je dijetalni šećer, pa korištenje neprobavljivih oligosaharida - kao što su rafinoza, fruktooligosaharidi, galaktozillaktoza, izomaltooligosaharidi ili transgalaktozilo-ligosaharidi - uzrokuju porast broja endogenih bifidobakterija i neke promjene kod bakterija mliječne kiseline. U radu su prikazani pregledi prebiotika i njihovih osobina kao i kriteriji za selekciju te sigurnost prebiotika i supstrata.There is an increasing consumer demand for natural products, particularly in the area of food or food additives. This has created some possibilities for the use of slowly absorbable and nonabsorbable sugars as substrates for lactic acid bacteria and as prebiotics for human nutrition. The human colon contains a high concentration of bacteria (10000000000000 per gram dry weight of colonic contents). Recent studies show that bifidobacteria and lactobacilli are among the common anaerobic bacteria in the human colonic microflora and may exert beneficial effects on the host. Dietary sugar source is the main factor affecting the multiplication of bifidobacteria in the human intestine. Consequently, the administration of nondigestible oligosaccharides such as raffinose, fructooligosaccharides, galactosyllactose, isomaltooligosaccharides, or transgalactosyloligosaccharied causes an increase in the number of endogenous bifidobacteria and some changes in lactic acid bacteria. In this paper prebiotics and theirs charasteristis were described as also criteria for selection and safety of prebiotics and substrates

Milk Powder as an Ingredient for the Production of Milk Chocolate

Čokolada je visokovrijedna namirnica koja osim osnovnih hranjivih sastojaka sadrži i niz bioaktivnih sastojaka, za koje je dokazan pozitivan učinak na ljudsko zdravlje. Zbog velikog izbora različitih čokoladnih proizvoda na tržištu te sve većih zahtjeva potrošača za kvalitetom proizvoda koje konzumiraju, sve se više pažnje posvećuje unaprjeđenju postupka proizvodnje prehrambenih proizvoda, pa tako i čokolade. Pritom je izrazito važno poznavati svojstva svake sirovine u tehnološkom procesu proizvodnje nekog proizvoda kako bi se moglo očuvati ili zaštiti njegove, potencijalno djelotvorne sastojke. Mlijeko u prahu je osnovni sastojak mliječne čokolade (oko 20% ukupne mase) koji određuje senzorski profi l čokolade (okus, tekstura) i utječe na njezina fizikalno-kemijska i reološka svojstva, posebice svojstva tečenja, koja su vrlo bitna prilikom lijevanja čokoladne mase u kalupe, kao i dražiranja čokoladom. Ranije se za proizvodnju čokolade tradicionalno koristilo punomasno mlijeko u prahu sušeno na valjcima, zbog velikog udjela slobodne mliječne masti, no budući da je danas sušenje na valjcima zastarjeli postupak, sve više se pažnje usmjerava na sušenje mlijeka u prahu raspršivanjem. Međutim, za razliku od sušenja na valjcima, sušenjem raspršivanjem nastaje prah malog udjela slobodne mliječne masti, što je poželjno za proizvodnju gotovo svih vrsta prehrambenih proizvoda, osim čokolade. Ovaj rad pruža pregled uporabe različitih vrsta mlijeka u prahu u proizvodnji mliječne čokolade te njihov utjecaj na reološka, fizikalno-kemijska i senzorska svojstva čokolade.Chocolate is a high nutritive value food product, that beside dietary nutrients, provides a wide array of bioactive constituents, which exhibit positive effects on human health. Due to a great number of various chocolate products available on the market and growing consumer demands regarding their quality, there is an increasing interest in improvement of production processes of food products, hence as well chocolate. At the same time, it is crucial knowing the properties of every ingredient in the production of a product, so that the potentially benefi cal compounds could remain preserved. One of the main ingredients of milk chocolate (constituting about 20% of total weight of chocolate) is milk powder, which determines the sensory profi le of milk chocolate (fl avor, texture) and infl uences their physico-chemical and rheological properties, especially flow poperties, that are important for chocolate molding as well as chocolate coating. Traditionally, for the production of milk chocolate, roller dryed whole milk powder was used, due to its high free milk fat content, but since the use of roller drying for the production of milk powder is decreasing, the attention is directed to spray drying for that purpose. However, in comparison to roller drying, spray dryed milk powder contains a low content of milk fat in the resulting product, which is desirable in the production of almost all food products, except chocolate. This paper provides an overview of the application of various types of milk powders in the production of milk chocolate, as well as their impact on the rheological, physico-chemical and sensory characteristics of chocolate

Influence of the homogenization pressure on the ice cream mix quality

U radu je ispitana primjena različitih tlakova homogenizacije na izgled i kvalitetu sladoledne smjese. Sladoledne smjese u kojima je izvor masti bio maslac, vrhnje ili biljna mast, uzimane su iz zrijača te podvrgnute različitim tlakovima homogenizacije nakon čega se pomoću mikroskopa sa skalarom određivala veličina masne globule. Tlakovi pod kojima su u sladolednim smjesama dobivene masne kapljice veličine od 1 - 2 μm bez nakupina, okarakterizirani su kao tlakovi pogodni za određenu vrstu masti i udio masti u toj sladolednoj smjesi. Kako se količina masti u sladolednoj smjesi povećava, tako se optimalni tlak homogenizacije mora smanjivati. Sladolednim smjesama s 2% biljne masti odgovara tlak homogenizacije od 200 bara, onima s 6% odgovara 190 - 200 bara, a smjesama s 8% biljne masti 170 bara. Smjesama u kojima je bilo 8% masti i gdje je izvor masti bio maslac, optimalan tlak je 190 - 200 bara. Za smjese s 10% maslaca optimalan tlak je 150 bara, a s 12% maslaca 135 bara. Optimalan tlak homogenizacije za smjese s 8% vrhnja je 200 bara, za 10% vrhnja 190 bara, za 12% vrhnja je 125 bara i za 14% vrhnja 90 bara.In this paper the suitability of different homogenization pressures on appearance and quality of ice cream mix was determined. The ice cream mix were taken from ageing tank, and depending on the source of fat in ice cream mix (butter, vegetable fat or cream) they were homogenized under different pressures. Afterwards, by microscope with scalar, fat globule size was determined. The homogenization pressures reduce the fat globule size to 1-2 μm without clumping and these pressures have been characterized as adequate pressures for specific type of fat and specific portion of fat in the ice cream mixture. The higher the fat in the mixture, the lower the pressure should be. The optimal pressure for ice cream mixture containing 2% vegetable fat was 200 bars, for 6% 190-200 bars, and for 8% 170 bars. The optimal pressure for ice cream mixture that contained 8% butter was 190-200 bars, for 10% 150, and for 12% 135 bars. For ice cream mixture containing 8% of cream, optimal pressure was 200 bars, 10% cream was 190, 12% cream was 125 bars and 14% cream was 90 bars

The application of ultrafiltration in the production of fermented milk products

U radu se navode bitne značajke razvojnog programa proizvodnje fermentiranih mliječnih proizvoda u kojem primjena ultrafiltracije (UF), a sve češće u kombinaciji s mikrofiltracijom (MF), ima glavnu ulogu: povećanje nutritivne i zdravstvene vrijednosti proizvoda, produženje trajnosti i postizanje proizvoda ujednačenog sastava i kakvoće. Iznose se prednosti primjene UF i MF za obradu mlijeka, osobito za obradu sirutke te uloga dobivenih koncentrata proteina pri proizvodnji fermentiranih mlijeka te svježih i mekanih sireva. Osnovna uloga UF je povećanje količine biološki najvrjednijih proteina sirutke koji također potiču rast uporabljenih kultura bakterija mliječne kiseline u proizvodu. Postižu se i neke tehnološke prednosti, te značajne uštede pri proizvodnji, osobito pri proizvodnji sira.This paper focuses on progress in the development programme of fermented milk product production in which the ultrafiltration (UF) very often in combination with microfiltration (MF), has a major role: the increase nutritional and health value of the product, prolongation of shelf life and obtaining a more stable quality of the final products. The advantages of the application of UF and MF for milk and especially for whey treatment and the role of obtained protein concentrates in production of fermented milks, fresh and soft cheeses are given. The essential role of UF is to increase the quantity of the most biologically valuable whey proteins which also stimulate the growth of lactic acid bacteria in fermented products. Some technological benefits and significant savings in production are also realized, especially in cheese production

Optimisation of minimal media for production of aroma compounds typical for fermented milk products

U radu je optimirana minimalna podloga na bazi mlijeka i laktoze na kojoj bakterije mliječne kiseline mogu proizvesti maksimalnu količinu hlapivih aromatskih tvari karakterističnih za fermentirane mliječne proizvode. Za pripreme podloga korišten je kazein, tri-natrij-citrat, laktoza, mineralne tvari mlijeka, proteini sirutke i mlijeko s 1,5 % m.m. Glavna razlika pojedinih podloga bila je u količini citrata i proteina sirutke. Fermentacija je vođena pri sobnoj temperaturi do pH vrijednosti 5. Uzorci su senzorski ocijenjeni metodom kvantitativne deskriptivne analize. U svim podlogama željena pHvrijednost, ovisno o količini citrata, postignuta je nakon 68 - 71 sati fermentacije. Fermentacija i nastanak aromatskih tvari bili su intenzivniji u podlogama koje su sadržavale proteine sirutke u usporedbi s podlogama koje su sadržavale samo kazein. Povećana količina citrata u podlogama pozitivno je djelovala na razvoj arome u supstratu. Citrat je povisio početnu pHvrijednost podloge, ali i djelovao kao pufer tijekom fermentacije, zbog čega je bila moguća dulja fermentacija i veća sinteza aromatskih tvari. Pri pH vrijednosti oko 5, aroma karakteristična za fermentirane mliječne proizvode je bila najizraženija, a kiseli okus manje dominantan. Supstrat s 0,25% citrata i 0,1% proteina sirutke, pri pH-vrijednosti 5, imao je najbolje senzorske karakteristike.The aim of this research was to optimize the composition of minimal growth media containing lactose and milk, in which lactic acid bacteria (LAB) would produce the maximum amount of volatile aroma compounds typical for fermented milk products. Ingredients used for the preparation of media were casein, tri-sodium-citrate, lactose, milk minerals, whey proteins and milk with 1.5% fat. The several prepared media differed mainly in the amount of citrate and whey proteins. Fermentation was carried out at room temperature until the media reached pH value of 5. Samples were evaluated for sensory characteristics using quantitative descriptive analysis (QDA). In all media the target pH was reached after 68-71 hours of fermentation, depending on citrate level. Fermentation and the production of aroma compounds were more intensive in media that contained whey proteins compared to media with only casein. Increased citrate level had a positive influence on the aroma production. Citrate increased the initial pH of the media and acted as a buffer during fermentation, which lead to longer fermentation and prolonged production of aroma compounds. At pH around 5, the desired cultured aroma was the most intensive, whereas sour taste was less dominant. The substrate with 0.25% citrate and 0.1% whey proteins, at pH 5, was rated as best regarding its sensory characteristics

Utjecaj enzimski hidrolizirane laktoze na fermentaciju i rast probiotičkih bakterija u sirutki

Taking in consideration the long time for whey fermentation using probiotic bacteria, the aim of this research was to determine if prior enzymatic hydrolysis of lactose influences microbial activities of Lactobacillus acidophilus La-5 or Bifidobacterium animalis subsp. lactis BB-12 in reconstituted sweet whey. During fermentation (at 37 °C), pH-value and viable cell counts were monitored. The fermented samples were sensory profiled. Lactose hydrolysis shortened the fermentation time of Lactobacillus acidophilus La-5 by 2 h, and viable cell count at the end of fermentation time was greater in hydrolyzed whey sample (~9.45 log10 CFU/mL) when compared with the control sample (~8.91 log10 CFU/mL). In contrast, lactose hydrolysis in whey did not enhance the activity of Bifidobacterium animalis subsp. lactis BB-12. Lactose hydrolysis had slightly influence on sensory score of fermented samples, probably due to sweetness that masked the acidic taste of the product.Uzimajući u obzir dužinu fermentacije sirutke probiotičkim bakterijama, cilj ovog rada bio je ispitati utječe li prethodna enzimska hidroliza laktoze na aktivnost bakterije Lactobacillus acidophilus La-5 ili Bifidobacterium animalis subsp. lactis BB-12 u rekonstituiranoj slatkoj sirutki. Tijekom fermentacije (pri 37 °C) praćena je promjena pH-vrijednosti i broj živih bakterijskih stanica. Fermentirani uzorci su senzorski analizirani. Hidroliza laktoze skratila je fermentaciju sirutke s Lactobacillus acidophilus La-5 za oko 2 sata, a broj živih bakterija na kraju fermentacije bio je nešto veći u hidroliziranoj sirutki (~9,45 log10 CFU/mL), u odnosu na kontrolni uzorak (~8,91 log10 CFU/mL). Međutim, hidroliza laktoze nije utjecala na aktivnost bakterije Bifidobacterium animalis subsp. lactis BB-12. Hidroliza laktoze neznatno je utjecala na senzorska svojstva fermentirane sirutke, jer vjerojatno stvorenu kiselinu prikriva osjet slatkoće

Sensory Evaluation of the Strawberry Flavored Yoghurt with Stevia and Sucrose Addition

As obesity is a growing problem in the world the target of food industries is to produce low calorie products safe for the human health. According to the non-caloric value of stevia and its beneficial influence on human health, there is a great possibility of its use in the food industry. Plain yoghurts were produced by fermentation with ABT-5 cultures (Lactobacillus acidophilus, Streptococcus thermophilus and Bifi dobacterium spp.) and flavored by addition of 0.2 mL/100 g strawberry aroma. Yoghurts were sweetened by the addition of 1) sucrose 2) stevia and 3) equal portion of sucrose and stevia in three different concentrations. Sensory properties of yoghurt where evaluated by panel using two methods; ranking test and 20 – point scaling system of weighted factors. Viscosity was measured by viscosimeter. According to sensory panel it was determined that 6 g of stevia was equal to 1000 g of sucrose. The best sensory evaluation had the yoghurts sweetened with addition of 4.5 g/100 g equal portions of sucrose and stevia. Addition of sweeteners weren’t influenced the apparent viscosity

Influence of sweetener stevia on the quality of strawberry flavoured fresh yoghurt

Stevia is a natural, non energetic sweetener, 200-300 times sweeter than sucrose, and is obtained by leaves extraction of the Stevia rebaudiana. According to the low energy value of stevia to sweeten food products, it is a great possibility of its use in the dairy industry. This study examined the differences in the sweetness of the strawberry flavoured yoghurt with the addition of sucrose, stevia and equal portions of sucrose and stevia; each combination was used at three different concentrations (3, 4.5 and 6 % / 100 g yoghurt). Stevia was diluted in a concentration which, according to the literature, matches the sweetness profile of sucrose. Viscosity of the yoghurts was determined by the rheometer, and sensory profiling of the products was evaluated by a panel using the ranking test and weighted factors methods. The level of sweetness of all yoghurt samples (using sucrose, stevia and mixture of sucrose and stevia) was judged by a test panel, and products were rated in the terms of degree of sweetness as sucrose > sucrose + stevia > stevia. The recommended level by panelists of any type or combination of sweeteners for strawberry yoghurt was 4.5 g sweetner/100 g. The apparent viscosity was lower in sucrose yoghurts compared to products made with stevia or stevia + sucrose which was also reflected in the sensory scores

The application of ultrafiltration in the production of fermented milk products

U radu se navode bitne značajke razvojnog programa proizvodnje fermentiranih mliječnih proizvoda u kojem primjena ultrafiltracije (UF), a sve češće u kombinaciji s mikrofiltracijom (MF), ima glavnu ulogu: povećanje nutritivne i zdravstvene vrijednosti proizvoda, produženje trajnosti i postizanje proizvoda ujednačenog sastava i kakvoće. Iznose se prednosti primjene UF i MF za obradu mlijeka, osobito za obradu sirutke te uloga dobivenih koncentrata proteina pri proizvodnji fermentiranih mlijeka te svježih i mekanih sireva. Osnovna uloga UF je povećanje količine biološki najvrjednijih proteina sirutke koji također potiču rast uporabljenih kultura bakterija mliječne kiseline u proizvodu. Postižu se i neke tehnološke prednosti, te značajne uštede pri proizvodnji, osobito pri proizvodnji sira.This paper focuses on progress in the development programme of fermented milk product production in which the ultrafiltration (UF) very often in combination with microfiltration (MF), has a major role: the increase nutritional and health value of the product, prolongation of shelf life and obtaining a more stable quality of the final products. The advantages of the application of UF and MF for milk and especially for whey treatment and the role of obtained protein concentrates in production of fermented milks, fresh and soft cheeses are given. The essential role of UF is to increase the quantity of the most biologically valuable whey proteins which also stimulate the growth of lactic acid bacteria in fermented products. Some technological benefits and significant savings in production are also realized, especially in cheese production